Japan says it expects China to expand its naval activities around Japan's shores, adding that Tokyo plans to build up its submarine fleet and other maritime defenses.

In an annual white paper released Tuesday, Japan's Defense Ministry also says it must keep a close watch on North Korea, which is developing a new ballistic missile that may be able to reach the U.S. territory of Guam.

The report predicts China will expand its naval activities in the East China Sea, where the two countries clashed last year after a Chinese fishing boat struck a Japanese coast guard vessel near a disputed island chain. Japan also expects China to continue passing through Japanese island chains into the Pacific Ocean and to press its claims to disputed areas in the South China Sea.

Japan's military says it will expand its submarine fleet from 16 vessels to 22 and strengthen radar capabilities along its southwestern coast.

The report says North Korea poses a threat to the region because of its nuclear weapons and ballistic missile programs, as well as aggressive behavior including an artillery attack on a South Korean island last year.

The annual report says a new North Korean missile, which is based on 1990s-era Soviet technology and called the Musudan, is being developed for launch from mobile platforms. It says the missile has a range of 2,500 to 4,000 kilometers, which would make it a threat to thousands of U.S. troops based in Guam.